Anosognosia in patients during transient hemispheric anesthesia

thesis Individualized functional mapping before epilepsy surgery is important, as the localization of function is variable among patients and may be influenced by epilepsy. The “golden standard” in testing language lateralization is the Wada test. During this procedure a major part of a hemisphere is temporarily inactivated. We can therefore expect contralateral hemiparesis and often (incomplete) hemianopia. Patients may not recall this hemiparesis when asked a few minutes after the test. The denial or inability to recognize the presence of such a major physical impairment can be seen as a form of anosognosia. The underlying mechanism for such anosognosia, lasting up to a few minutes after hemispheric anesthesia during the Wada test, has not been studied. The current study will investigate how often a patient, a few minutes after the Wada injection, is not aware of an inability during the test and if this anosognosia can be profiled. We expect that anosognosia will occur when the non-language-dominant hemisphere is anesthetized and the patient has a pre-existing deficit in executive functioning. In addition to testing this hypothesis, explorative research will also be conducted to see if there are multiple remarkable observations to form new hypotheses in the future. Video recordings of the Wada tests were reviewed. Symptoms of anosognosia was present in 70% of the cases. We could not find an association between a range of presumed predictive variables and the occurrence of anosognosia. Only a trend for male sex is found.